Enter the missing reasons for the following two-column proof. Given: M is the midpoint of C D ; C M = 3 x − 10 ; M D = 6 x − 22 Prove: x = 4 Statement Reason M is the midpoint of C D ; C M = 3 x − 10 ; M D = 6 x − 22 1. ? C M = M D 2. ? 3 x − 10 = 6 x − 22 Substitution − 3 x − 10 = − 22 Subtraction Property of Equality − 3 x = − 12 3. ? x = 4 Division Property of Equality